little_paco
Member
I've been wandering how a compressor work since a long time. After reading and looking at schematics i tried to make my own.
Here is the result:
https://sites.google.com/site/nanotweed/home/ldr_compressor_xp
Is this the best compressor on earth certainly not, but it was fun to build and it use simple parts execpt for a LDR. It might interest some people....
In terms of performance here are some measurement:
![Reponse_compresseur.jpg Reponse_compresseur.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/54/54082-76f4c064f67a6e5d3bc2601ee4d578bd.jpg)
A little description of the parts used:
part 1 a buffer with a tlo72 (to have high input impedance)
Part 2 a attenuator using the LDR
Part 3 a rectifier and a diode
Part 4 an enveloppe filter to drive the next stage next stage, and also an offset correction
Part 5 the heart of the system: a log converter
Vout is proportional to log (VThreshold/Venv)
The output is -2,9V every decade.
This feed part 6:
an amplifier to set the slope:
A diode (thresholdless)
An enveloppe dectector to set release and attack time
This control voltage feed the part 2 theres also a bias level to set the diode on the edge of blinking.
Here is a picture of the board just to for fun:
![IMG_20221228_113031.jpg IMG_20221228_113031.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/54/54083-d4f8cd8b303c8a240ed6e481c2875427.jpg)
I'll come back later to complete the post.
Here is the result:
https://sites.google.com/site/nanotweed/home/ldr_compressor_xp
Is this the best compressor on earth certainly not, but it was fun to build and it use simple parts execpt for a LDR. It might interest some people....
In terms of performance here are some measurement:
![Reponse_compresseur.jpg Reponse_compresseur.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/54/54082-76f4c064f67a6e5d3bc2601ee4d578bd.jpg)
A little description of the parts used:
part 1 a buffer with a tlo72 (to have high input impedance)
Part 2 a attenuator using the LDR
Part 3 a rectifier and a diode
Part 4 an enveloppe filter to drive the next stage next stage, and also an offset correction
Part 5 the heart of the system: a log converter
Vout is proportional to log (VThreshold/Venv)
The output is -2,9V every decade.
This feed part 6:
an amplifier to set the slope:
A diode (thresholdless)
An enveloppe dectector to set release and attack time
This control voltage feed the part 2 theres also a bias level to set the diode on the edge of blinking.
Here is a picture of the board just to for fun:
![IMG_20221228_113031.jpg IMG_20221228_113031.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/54/54083-d4f8cd8b303c8a240ed6e481c2875427.jpg)
I'll come back later to complete the post.
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